Flexible Reusable Outer Covers For Disposable Absorbent Inserts

ABSTRACT

Flexible reusable outer covers for disposable absorbent inserts.

FIELD OF THE INVENTION

The present invention relates generally to the field of diapers and moreparticularly, to flexible reusable outer covers for disposable absorbentinserts.

BACKGROUND OF THE INVENTION

Several designs of diapers that include a reusable outer cover beenmanufactured and marketed. However, these designs have less flexiblereusable outer covers.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a wearable absorbent article as it mightappear being worn by a wearer about the lower torso;

FIG. 2A is a plan view of an outer cover opened and laid flat, outersurface facing the viewer;

FIG. 2B is a plan view of an outer cover opened and laid flat, innersurface facing the viewer;

FIG. 3 is a perspective view of a disposable absorbent insert shownapart from an outer cover, as it might appear in a free-standing,relaxed state;

FIG. 4 is a plan view of a disposable absorbent insert shown stretchedout and laid flat, body-facing surfaces facing the viewer;

FIG. 5 is a front view of a plunger blade used for the upper movabletest fixture in the Bending Stiffness Test;

FIG. 6 is a side view of a plunger blade used for the upper movable testfixture in the Bending Stiffness Test;

FIG. 7 is a side view of a lower stationary test fixture in the BendingStiffness Test.

DETAILED DESCRIPTION OF THE INVENTION

Definitions

For purposes of this description, the following terms have the meaningsset forth:

“Absorbent insert” and “insert” mean a component of a wearable absorbentarticle that is adapted to contain and/or absorb urine, feces, menses orany combination thereof, and is adapted to be installable and removableas a modular unit, from an outer cover. Herein, an absorbent insert mayalso be referred to as an “absorbent assembly”. The terms “absorbentinsert,” “insert” and “absorbent assembly” may be used interchangeablyherein.

“Chassis” means a component of a wearable absorbent article that isadapted to be worn about the lower torso of a wearer, and is adapted tosupport an absorbent insert and hold the insert next to the wearer'sbody. Herein, a chassis may also be referred to as an “outer cover”. Theterms “outer cover” and “chassis” are interchangeable for purposesherein.

“Disposable”, when referring to an absorbent insert, means that theabsorbent insert is not adapted or intended to be effectively sanitarilylaundered in an ordinary household laundering process and ordinaryhousehold equipment, and thereby is ordinarily unsuitable for sanitaryand effective reuse so as to provide as-new intended functions andperformance, following soiling by exudates and removal from an outercover. By way of non-limiting examples, effective laundering may befrustrated or prevented, causing the insert to be disposable, byinclusion of materials and/or construction: that do not retain theirsubstantial as-new physical shape or structure through ordinaryhousehold laundering and drying so as to be effective as-new in reuse;that absorb aqueous liquids and cannot be sufficiently dried/dehydratedin ordinary household drying equipment and ordinary drying cycles so asto be effective as-new in reuse; that dissolve or substantially degradein ordinary household laundering or drying, causing the insert to besubstantially damaged or rendered useless; and/or that cannot beeffectively cleaned of exudate material through ordinary laundering, soas to be sanitary and otherwise acceptable for re-use.

“Fastener component” means any component of a system that effectsremovable fastening, attachment or holding of a first structure to asecond structure. The system may have a single fastener component, forexample, an adhesive patch on the first structure adapted to adhere toone or more types of surfaces on the second structure, or a hook, orpatch of hooks on the first structure, adapted to catch on one or moretypes of surfaces on the second structure. By way of further example,any structure such as a pocket, strap, hook, buckle, etc. on a firststructure adapted to capture and retain, in whole or in part, the secondstructure, is a “fastener component” as used herein. The system also maycomprise two or more fastener components, for example, respectivecomponents of a hook-and-loop fastening system (such as VELCRO),respective surfaces having a cohesive material applied thereto; male andfemale snap fastener components, a button and button hole, slot or loop,other fastenably cooperating elements, etc. Other examples of fastenercomponents include zipper components, “zip lock” engaging components,loops, posts, pockets, bands or straps, microfasteners, macrofasteners,and fastener components such as described in U.S. Pat. Nos. 6,936,039;6,893,388; 6,669,618; 6,432,098; and 6,251,097, and U.S. PublishedApplications, Pub. Nos. 2005/0234419; 2005/0215971; 2005/0215970;2005/0130821; 2004/0023771; 2003/0233082; 2003/0119641; 2003/0088220;and 2002/0169431.

“Lateral” (and forms thereof), with respect to a wearer, means along adirection generally transverse or across the direction extending fromthe front to the rear of the wearer, or vice versa. With respect to acomponent of a wearable absorbent article, “lateral” (and formsthereof), means along a direction generally transverse or across thedirection extending along the component as it would be properly situatedon a wearer, from the front to the rear of the wearer, or vice versa.

“Longitudinal” (and forms thereof), with respect to a wearer, meansalong a direction generally extending from the front to the rear of thewearer, or vice versa. With respect to a component of a wearableabsorbent article, “longitudinal” (and forms thereof), means along adirection generally extending along the component as it would beproperly situated on a wearer, from the front to the rear of the wearer,or vice versa.

“Outer cover” means a component of a wearable absorbent article that isadapted to be worn about the lower torso of a wearer, and is adapted tosupport an absorbent insert and hold the insert next to the wearer'sbody. Herein, an outer cover may also be referred to as a “chassis”. Theterms “outer cover” and “chassis” are interchangeable for purposesherein.

“Reusable”, when referring to an outer cover, means an outer cover thatis adapted to permit removal of at least a first insert, and replacementthereof with at least a second insert, without substantial destructionof any components of the outer cover that are necessary to provide thesubstantial as-new functionality of the outer cover, and without thenecessity of any repair or reconstruction following such insertreplacement.

“Use,” with respect to an outer cover, means one event of the wearing ofthe outer cover until the time an absorbent insert is replaced.

“User” means a caregiver or other person who may apply a wearableabsorbent article to a wearer. Where the wearer is capable of donningthe wearable absorbent article him/herself, the wearer is also a “user”.

“Wearer” means a person who may wear a wearable absorbent article asdescribed herein.

“Wearable absorbent article” means any article designed to be worn aboutthe lower torso and to contain and/or absorb urine, feces, menses or anycombination thereof. “Wearable absorbent article” includes but is notlimited to baby or children's diapers (of the “tape”-fastenable,otherwise fastenable, “pull-up” or any other variety), training pantsand adult incontinence pants, briefs and the like.

Two-Piece Wearable Absorbent Articles

FIG. 1 depicts an example of a wearable absorbent article 10 havingcertain features, as it might appear while being worn by a wearer.Wearable absorbent article 10 may include an outer cover 20, havingfront waist edge 21, rear waist edge 22, and a pair of leg opening edges23.

FIGS. 2A and 2B depict an outer cover 20 as it may appear opened andlaid flat. In FIG. 2A, the outer, i.e., garment-facing, surfaces ofouter cover 20 face the viewer; in FIG. 2B, the inner, i.e.,wearer-facing, surfaces of outer cover 20 face the viewer. Front andrear waist edges 21, 22 are depicted at the top and bottom of thedrawings, respectively. Outer cover 20 may have crotch region 26, frontregion 27, rear region 28 and a pair of fastening ears 29 laterallyextending from rear region 28. Outer cover 20 will have a length LC fromthe forwardmost portion of front waist edge 21 to the rearwardmostportion of rear waist edge 22, and an outer cover lateral axis 45equally dividing this length. Thus, front region 27 is forward of outercover lateral axis 45, and rear region 28 is rearward of outer coverlateral axis 45. Outer cover 20 may have disposed thereon one or moreinsert fastener components such as front and rear insert fastenercomponents 33, 32.

FIG. 3 depicts a disposable absorbent insert 50 that may form an innercomponent of the wearable absorbent article 10, shown in perspectiveview as it might appear in a free-standing, relaxed state, apart fromouter cover 20. Insert 50 may be designed to contain and/or absorb bodyexudates, and may be made of pliable materials as will be describedfurther below. Insert 10 has forward region 54 and rearward region 55,and may include front fastener component 56 and rear fastener component57. Insert 10 may include a body-facing liner or topsheet 51, outerliner or backsheet 52, and a pair of standing cuffs 53. Referring toFIG. 4, insert 50 will have a length L from the forwardmost portion offorward region 54 to the rearwardmost portion of rearward region 55, andan insert lateral axis 70 equally dividing this length. Thus, forwardregion 54 is forward of insert lateral axis 70, and rearward region 55is rearward of insert lateral axis 70.

Referring to FIGS. 2B and 3, insert 50 may have rear fastener component57 disposed thereon. Alternatively, or in addition, outer cover 20 mayhave rear insert fastener component 32 disposed thereon. Similarly,insert 50 may have front fastener component 56 disposed thereon.Alternatively, or in addition, outer cover 20 may have front insertfastener component 32 disposed thereon. If a two-component fasteningsystem is used, fastener component pairs 57, 32 and 56, 33 may becooperating components that effect fastening therebetween when theserespective components are brought together. Thus, in the exampledepicted, in order to install absorbent insert 50 into outer cover 20, auser may lay outer cover 20 flat, inner surface 25 facing up, stretchand orient insert 50 such that rear fastener component 57 faces rearinsert fastener component 32 and front fastener component 56 faces frontinsert fastener component 33, and bring these respective fastenercomponent pairs 57, 32 and 56, 33 together to effect fasteningtherebetween.

If it is desired that outer cover 20 be reusable, for outer cover 20 toremain substantially sanitary and useful (without requiring launderingor disposal) after removal and replacement of an insert, it may bedesired that all parts of outer cover 20 remain substantially unsoiledafter an exudation of waste (especially fecal matter) by the wearer.Thus, it may be desired that when insert 50 is installed within an outercover 20, there is no non-removable portion or component of outer cover20 that lies over or covers a substantial portion of wearer-facingsurfaces of insert 50 (expressed differently, no non-removable portionor component of outer cover 20 is situated between a substantial portionof insert 50 and the wearer when the wearable absorbent article isworn), at least in the areas proximate to wearer body features thatdischarge exudates. Thus, it may be desired that outer cover 20 includeno non-removable cover sheet or the like that covers or containssubstantial portions of wearer-facing surfaces of insert 50 within outercover 20, nor any overlying structures such as pockets, straps or flapsthat substantially wrap or cover the insert proximate to exudatedischarge points, or lie substantially between insert 50 and thewearer's anus and/or genitals, when the wearable absorbent article isworn. If outer cover 20 lacks such overlying structures, this mayincrease the likelihood that the wearer's exudates will contact onlyinsert 50, and not portions of outer cover 20.

Referring to FIGS. 1, 2A and 2B, it can be seen that wearable absorbentarticle 10 may be placed on a wearer by wrapping outer cover 20 betweenthe wearer's legs and under the buttocks such that crotch region 26 isbetween the wearer's legs, bringing front waist edge 21 and rear waistedge 22 into the positions approximately as shown in FIG. 1, and thensecuring fastening ears 29 to front region 27, thereby forming apant-like garment about the wearer as suggested in FIG. 1. When insert50 has been installed into outer cover 20, insert 50 will then bedisposed within outer cover 20, next to the wearer, with the standingcuffs 53 oriented and extending longitudinally adjacent the innerportions of leg edges 23 (i.e., longitudinally between the wearer'slegs).

Examples of Possible Outer Cover Details

Fastening System

Referring to FIGS. 2A and 2B, to enable fastening of fastening ears 29to front region 27, fastening ears 29 may have outer cover fastenercomponents 30 disposed thereon. Alternatively, or in addition, frontregion 27 may have disposed thereon one or more receiving fastenercomponents 31 disposed thereon. Fastener components 30, 31 may beselected so as to be cooperative to effect fastening of ears 29 to frontregion 27.

In one example, outer cover fastener components 30 may include a patchof hooks, and receiving fastener component 31 may include a patch ofloops. An example of a suitable hook-and-loop fastening system is aVELCRO system (a product of Velcro Industries B.V.) A hook-and-loopfastening system provides certain advantages. Because the respectivehook and loop components are supplied in sheet form, they may be cutinto suitably shaped patches that can be affixed to a cloth or nonwovensubstrate by various mechanisms, including adhesive bonding, mechanicalbonding, ultrasonic bonding, sewing, stitching, serging, edging, and thelike. If patches of hooks or loops are affixed to fastening ears 29 toform outer cover fastener components 30, as suggested by FIG. 2B, alaterally extended patch of cooperating hook or loop material can beaffixed to outer cover front region 27 to form a receiving fastenercomponent 31, as suggested by FIG. 2A. By providing for fastening ofears 29 to front region 27 at laterally varying locations thereon, thisarrangement provides for easy and simple adjustability of waist openingsize of the wearable absorbent article.

In another example, as noted above, the outer cover fastening system mayinclude other types of fastener components. To provide for waist openingsize adjustability, fastener components disposed on fastening ears 29that cooperate with extended surfaces or multiple cooperating fastenercomponents disposed on front region 27 may be used. Receiving fastenercomponents may be multiply disposed on front region 27 in laterallyarranged, varying locations, allowing for fastenability of respectiveears 29 to front region 27 at laterally varying locations.

Referring to FIG. 2B, outer cover 20 also may have one or morerespective fastener protectors 39 disposed thereon. This feature mayprevent fastener components having features likely to randomly andunintentionally engage and catch on portions of the outer cover, orother articles, during storage, carrying, laundering and similar/relatedactivities, from doing so, thereby avoiding potential bunching,entangling and/or damage to either outer cover 20 or other articlesduring such activities. For example, if fastener components 30 arepatches of hooks, appropriately placed fastener protectors 39 mayinclude patches of corresponding loops. This will enable the user tofold ears 29 over to engage them with fastener protectors 39, therebyholding them in the folded-over position such that hooks thereon will beconcealed and prevented from snagging other articles when outer cover 20is not being worn.

Outer cover 20 also includes respective front and rear visual indicia73, 74 disposed on the front region 27 and rear region 28, respectively.Respective visual indicia disposed on insert 50 and outer cover 20 maybe adapted to provide a visual cue to the user of correct/optimalorientation and placement of insert 50 within outer cover 20.

Materials

Outer cover 20 and/or layers or portions thereof may be made of anyknitted, woven or nonwoven textile or textile-like material that isappropriately compatible with skin of the intended wearer(s). Outercover 20 may be constructed of durable and/or semi-durable materials.Generally, only for purposes of reference in this description, “durable”refers to a woven or knitted textile material of any kind that may beused as a component of a washable clothing article. As used herein,“durable” includes materials which are “launderable” as defined anddescribed in co-pending U.S. applications Ser. Nos. 12/687,412,12/687,528, and 12/687,425, entitled, respectively, “REUSABLE OUTERCOVER FOR AN ABSORBENT ARTICLE,” “REUSABLE OUTER COVER FOR AN ABSORBENTARTICLE HAVING ZONES OF VARYING PROPERTIES,” and “LEG AND WAISTBANDSTRUCTURES FOR AN ABSORBENT ARTICLE,” by Donald C. Roe (Procter & GambleAttorney Docket Nos. 11557, 11558 and 11559), filed on the same dayhereof. Generally, only for purposes of this description, “semi-durable”refers to a nonwoven material or laminate thereof that when used as anouter cover material can withstand more than one use with an insertwithout losing its structural integrity to an extent that renders itunserviceable. As used herein, “semi-durable” includes materials whichare “laundering resistant” as defined and described in the co-pendingU.S. applications identified immediately above. Thus, outer cover 20 maybe constructed of materials and construction that make it reusableand/or washable.

Durable materials of which outer cover 20 may be constructed may includeany natural or synthetic textile materials known in the diaper, pant,underwear, performance clothing, sport clothing, or general clothing ortextile arts. Durable materials may include woven or knitted textilesmade of natural fibers such as cotton, linen, wool, bamboo, hemp, silk,rayon, and the like, as well as blends of any of these fibers with anyother(s), or with synthetic fibers. Examples of synthetic fiberssuitable for use as components of durable materials include polyester,nylon, spandex and/or other elastomer fibers. Durable outer covermaterials also may include breathable water repellent materials such asGORE-TEX (a product of W. L. Gore & Associates, Inc., Elkton, Md.),fabrics comprising microencapsulated phase-change polymer materials suchas OUTLAST COMFORTEMP fabrics (products of Outlast Technologies,Boulder, Colo.—see U.S. Pat. No. 6,514,362 and U.S. Pat. No. 6,207,738,for example), COOLMAX (a product of Invista, Wichita, Kans.), and thelike.

Suitable durable materials may be formed in any weave or knit fabricform, including birdseye fabric, terry, fleece, flannel, knits, stretchknits, sherpa, suedecloth, microfleece, satin, velour, Burley knits,etc. Suitable examples include POLARTECH POWER DRY, POWER STRETCH andWIND PRO (products of Polartec, LLC, Lawrence, Mass.). Knitted textiles,which may be more inherently stretchable and elastic than woven ornonwoven materials, may impart better fit, comfort and/or appearance tothe outer cover. Incorporation of fibers of spandex or other elastomeralso may also enhance stretchability and elasticity, and thereby impartbetter fit, comfort and/or appearance to the outer cover, than textilesnot including such elastomeric fibers.

Specific suitable examples for durable outer cover materials includejersey knits of blends of: rayon (93%) and spandex (7%) fibers; modal(94%) and spandex (6%) fibers; cotton and spandex fibers; and bamboo andspandex fibers. Materials that have stretch capability of equal to orgreater than about 2× may be desired. Suitable examples of materials mayhave basis weights of about 0.09-0.15 gram/in.² per layer, or otherbasis weights.

Durable outer cover materials may be selected to impart desired comfort,appearance and performance to outer cover 20. In some circumstances itmay be desired to select durable outer cover materials which aresufficiently inexpensive to allow for disposal, if soiled extensively ordamaged, with minimized issues of cost or conscience.

Semi-durable outer cover materials may include any natural or syntheticnonwoven web and/or film materials known in the diaper or pant arts.Semi-durable materials of which outer cover 20 may be constructed mayinclude non-woven web materials of polypropylene and/or polyethylenefibers, polyester fibers, and any other synthetic fibers used to formnonwoven web materials used as components of disposable diapers, andblends thereof. Natural fibers such as cotton, linen, wool, bamboo,hemp, silk, rayon, and the like may be blended with synthetic fibers toform such a nonwoven web suitable as a component layer of outer cover20.

Non-limiting examples of fibers, nonwovens and laminates of nonwovensand films that might be considered for use as semi-durable outer covermaterials may be found in U.S. Pat. Nos. 7,223,818; 7,211,531;7,060,149; 6,964,720; 6,905,987; 6,890,872; 6,884,494; 6,878,647; and5,518,801; and U.S. Published Applications Nos. 2008/0319407;2008/0045917; 2007/0293111; 2007/0287983; 2007/0287348; 2007/0249254;2007/0203301; and 2005/0164587.

Semi-durable outer cover materials also may be selected to impartdesired comfort, appearance and performance to outer cover 20. In somecircumstances it also may be desired to select semi-durable outer covermaterials which are sufficiently inexpensive to allow for disposal, ifsoiled extensively or damaged, with minimized issues of cost orconscience.

The outer cover also, or additionally, may include a laminated orsubstantially separate film layer, which may be elastic, to provideenhanced liquid penetration resistance and/or elastic properties.Elastic properties also can be added or enhanced via the addition ofother materials to the outer cover in layer, band or strip fashion,including elastic strands, bands, scrims, and the like. A film layer maybe laminated with a durable material or semi-durable material. A filmlayer may include an elastomer based on KRATON (a product of KratonPolymers U.S., LLC, Houston, Tex.), or by way of further example,VISTAMAXX available from ExxonMobil Chemical Company, Houston, Tex.;FLEXAIRE, EXTRAFLEX or FABRIFLEX (products of Tredegar Film ProductsCorporation, Richmond, Va.), and various latex-free elastomeric sheetsavailable from Fulflex Elastomerics Worldwide (Greenville, Tenn.).

Inclusion of an elastomeric material, either as a fibrous component of acloth or nonwoven layer, or as a film layer, provides for improvedstretchability and elasticity where it may be deemed useful toaccommodate the wearer's anatomy and movements, such as over thewearer's buttocks and/or around the waist areas, and improved fit andcomfort. Additionally, where a film layer may be included, it may impartadditional liquid containment capability to the outer cover. A filmlayer may include a film that is substantially liquid impermeable, butvapor permeable, so as to provide breathability and reduce humiditywithin the outer cover while it is being worn, reducing chances forover-hydration of the skin where liquid containment capability isdesired. A breathable film also may be provided by mechanicallyperforating or aperturing a film by various processes. Examples of suchprocesses are described in co-pending U.S. applications Ser. Nos.12/366,825 and 12/534,353.

Referring to FIG. 2A, in one example outer surface 24 may be formed by afirst layer of a durable or semi-durable material. The material selectedmay include fibers having hydrophobic properties, providing enhancedliquid containment attributes to such first layer. In another example,however, it may be desirable in some circumstances for the selectedmaterial to include hydrophilic fibers, or fibers treated to behydrophilic, so as will cause the material to more readily absorb and/ortransmit liquid therethrough. This may serve to provide supplementalabsorbency within the outer cover for the event in which liquid exudatesescape the insert, or to provide one way of communicating to the userthat liquid exudates have escaped the insert. Additionally, in somecircumstances it may be desirable that the material selected have softtactile properties so as to have a pleasant feel that the user and/orwearer find attractive. The material also may be selected so as to havea desired appearance, including but not limited to coloration, sheen,texture, etc.

Outer cover 20 may be formed of a single layer of a durable orsemi-durable material, or may have two or more layers in the frontregion 27 and/or rear region 28. Accordingly, referring to FIG. 2B, inanother example inner surfaces 25 may be formed by a second layer of adurable or semi-durable material. The material selected may includefibers having hydrophobic properties, providing enhanced liquidcontainment attributes to the second layer. In another example, however,it may be desirable in some circumstances for the selected material toinclude hydrophilic fibers, or fibers treated to be hydrophilic. Thismay be desired in some circumstances to cause the material forming innersurfaces 25 to more readily absorb liquid, or transmit liquidtherethrough. This may serve to provide supplemental absorbency withinthe outer cover for an event in which liquid exudates escape the insert,reducing the likelihood that the outer cover will leak. Alternatively,it may provide one way of communicating to the user that liquid exudateshave escaped the insert, by causing wetness to be transmitted through tothe outer cover outer layer such that wetness is visible on outersurfaces. Alternatively, it may serve to provide a layer that tends todraw moisture away from the skin, for a drier, more comfortable feel.

Additionally, in some circumstances it may be desirable that thematerial(s) selected for inner surfaces 25 have soft tactile propertiesso as to have a pleasant feel against the skin, particularly in areaswhere no portion of an insert is expected to be present between theouter cover and the wearer's skin.

In another example, the second layer of material may be formed of atextile material having enhanced elasticity, such as by inclusion offibers of an elastomeric material (such as spandex). In another example,an intermediate film layer may be included, laminated or not laminatedwith another layer.

Forming the outer cover 20 of more than one layer, for example, two, ormore, layers, as described above, may provide various benefits. A secondlayer (and any additional layers) may provide supplemental tensilestrength in both the lateral and longitudinal directions across theouter cover 20. Additionally, a first layer may be selected for a firstset of properties, and a second layer may be selected for a second setof properties. For example, material forming a first layer may beselected for having comparatively greater elasticity and a particulartexture, color and/or other appearance-related properties, and materialforming a second layer may be selected for having comparatively greaterhydrophobicity, hydrophilicity and/or softness to the skin for purposesof an inner layer, the two layers in combination imparting a combinationof desirable attributes to the outer cover. For example, the inner layermay be formed of material(s) and/or treated to be more hydrophilic so asto provide for absorbency and reduced chances of fluid runoff (leakage),while the outer layer may be formed of material(s) that are morehydrophobic, so as to, e.g., resist environmental soiling, or resistliquid transmission from the inner layer to the outer layer.Additionally, a plurality of layers may better serve to conceal bumps,corners, seams or other features of an insert, as compared with a singlelayer, for a smoother, more attractive appearance.

Reusable outer covers designed to hold disposable absorbent inserts arecomfortable and fit the contours of the wearer's body. Outer covermaterials should have a low bending stiffness to enable them to adaptand conform to the wearer's anatomy and move with the wearer's body witha minimum of resistance, leading to a comfortable fit whether the weareris quiescent or active. A conforming fit also allows the perimeterregion of the outer cover, which may include elasticized leg or waistbands, to remain in a desirable relative orientation and location on thewearer's body to prevent leakage of bodily exudates.

The outer cover “as used” may be constructed of a unitary element, suchas a single layer of material or a bonded laminate of two or morematerials. Alternatively, the outer cover may be constructed of two ormore discrete layers of material, having similar or differentproperties. In the latter case, the two or more discrete layers ofmaterial may be joined together at or near the perimeter of the article,e.g., in a seam or attachment point of a leg or waistband, or may bejoined at one or more discrete locations in the article, such as atlocations where a fastening element is affixed to the inner or outersurface of the outer cover. Regardless of the number of layers, or“stack up”, the bending stiffness of the “as used” stack up of the outercover material may be less than about 0.20 N, or 0.19 N, in the BendingStiffness test described herein. If the outer cover includes more thanone discrete layer (i.e., separable from another layer of the outercover over a sufficient area to enable the Bending Stiffness test to beperformed, the Bending Stiffness of at least one of the layers may beless than about 0.10 N or less than about 0.08 N. In some embodiments,each layer may have a Bending Stiffness of less than about 0.10 N or0.08 N.

The addition of a fastening element to the wearer-facing surface of theouter cover may require, in some embodiments, a higher Bending Stiffnessto create additional support to carry the loading force transferred fromthe insert to the outer cover material. The Bending Stiffness of the “asused” stack up of outer cover material to which an insert-to-outer covermaterial is affixed may be less than about 0.30 N.

Table 1, shown below, shows test data for outer cover flexibility fromthe testing of whole outer cover samples of four current marketabsorbent articles and from a Test Article. The four current marketproducts were the gDiaper (size large, from gDiapers, Inc. of Portland,Oreg., United States purchased in April 2010 from www.gdiapers.com), theGroBaby/Gro Via (from The Natural Baby Co. of Bozeman, Mt., UnitedStates purchased in April 2010 at www.thenaturalbabyco.com), the BummisSuperBrite (size large, from Bummis, Inc., of Montreal, Quebec, Canadapurchased in April 2010 from www.thenaturalbabyco.com), and theDiaperaps (size large, from Diaperaps: Baby's Organic Nursery, GranadaHills, Calif., United States purchased in April 2010 fromwww.babysorganicnursery.com).

The Test Article outer cover was configured according to embodiments ofthe present disclosure, with an outer layer material and inner linermaterial both made of 93% Modal and 7% Spandex, available as codeE.n.n-14 from Koshtex, Los Angeles, Calif., United States, outer coverhooks made of 100% nylon, available as sewable hooks from PerfectekPlus, Huntington Beach, Calif., United States, outer cover landing zone,available as code 960E from Aplix, Paris, France, and insert landingzone made of 100% nylon, available as standard sew on material fromTouchtape, St. Augustine, Fla., United States.

TABLE 1 Test gDiaper GroBaby Bummis Diaperaps Article outer outer outerouter outer cover cover cover Cover cover Bending 0.355 0.381 0.2610.206 0.183 stiffness peak force (Newtons)

For the test data in Table 1, for each type of outer cover, ten sampleswere tested, and the average was reported. The outer cover bendingstiffness peak force was measured by using the Bending Stiffness Test,disclosed herein. Also, for the Test Article, the bending stiffness peakforce of the outer layer material was measured using the BendingStiffness Test, and was found to be 0.070 Newtons. Further, for the TestArticle, the bending stiffness peak force of the inner liner materialwas measured using the Bending Stiffness Test, and was found to be 0.056Newtons.

In addition to forming differing layers of differing materials, it maybe desirable to form a single layer of differing materials, for example,differing materials in the respective front, crotch and/or rear regionsof the outer cover. Such differing materials may be joined at a seamsuch as inner seam 40 and/or outer seam 41. For example, the materialpredominately forming the inner surface of rear region 28 may beselected primarily for its elasticity features, which may better serveto provide snug fit about wearer body contours and accommodate wearermovement (i.e., about the buttocks and hips). By comparison, thematerial predominately forming the inner surface of front region 27and/or crotch region 26 might be selected primarily for itshydrophobicity or hydrophilicity, which may better serve to containliquid exudates.

Layers or other elements of the outer cover may be joined to each othervia any suitable mechanism, including, for example, adhesives,mechanical bonding, ultrasonic bonding, sewing, stitching, serging,edging, and the like.

Additionally or alternatively to the constructions and materialsdescribed above, the outer cover may be constructed and may includematerials and features as described in co-pending U.S. applications Ser.Nos. 12/687,412, 12/687,528, and 12/687,425, entitled, respectively,“REUSABLE OUTER COVER FOR AN ABSORBENT ARTICLE,” “REUSABLE OUTER COVERFOR AN ABSORBENT ARTICLE HAVING ZONES OF VARYING PROPERTIES,” and “LEGAND WAISTBAND STRUCTURES FOR AN ABSORBENT ARTICLE,” by Donald C. Roe(Procter & Gamble Attorney Docket Nos. 11557, 11558 and 11559), filed onthe same day hereof.

Elasticized Waistbands, Leg Bands

Referring again to FIGS. 1, 2A and 2B, front waist band portion 34, rearwaist band portion 35, and leg band portions 36 are depicted. One ormore of these band portions 34, 35, 36 may be formed of one or morestrands or strips including an elastomeric material such as spandex or ablend of spandex and other fibers, enveloped by a nonwoven or textilematerial, which may include the edges of the material forming the innerand/or outer layers of outer cover 20, to form and elasticize therespective band portions. The elastic material may be affixed to orwithin an outer cover layer in a strained condition, or at zero appliedstrain. Textile material(s) enveloping the elastic strand(s) or strip(s)may be sewn around elastic strand(s) or strip(s) to hold them in placewithin the respective band portions. If the elastic material is strainedprior to, and while, being enveloped and affixed to form these bandportions during the manufacturing process, upon relaxation theenveloping material and adjacent outer cover material may be caused togather and form ruffles 37 therealong, which constitute gathered outercover material. This can serve to promote snug fit, wearer comfort andappearance. The band portion may be disposed along the edge of the outercover, and in some circumstances it may be desired to have the bandportion situated along substantially the entire length of the leg and/orwaist openings so as to form bands that substantially or completelyencircle the wearer's legs and/or waist while outer cover 20 is worn.The gathered material within ruffles 37 can serve to accommodatestretching of waist band portions 34, 35 and leg band portions 36. Thisarrangement including elasticized leg band portions 36 as described, notonly may provide for better fit about the wearer's legs, but also mayenable the outer cover 20, when formed of appropriately sized and shapedmaterial, to form a pouch-like structure 75 in the crotch region (seeFIG. 1) when worn, which may serve to provide space within the outercover to accommodate the insert 50 (FIG. 3) and help hold it in placewithin outer cover 20, in a substantially laterally centered positionwithin the crotch region. This may be deemed advantageous in examples inwhich an insert 50 is attached within outer cover 20 by fastenercomponents only located proximate to the respective ends of insert 50,and not at any longitudinally intermediate locations, as describedfurther below. Alternatively, or additionally, the elastic strands orstrips in waist band portions 34, 35 and leg band portions 36 may beaffixed within the outer cover only at or near their respective ends,e.g., within a pouch, tube or envelope structure formed of outer covermaterial—referred to herein as a “drawstring elastic”. This will allowthe elastic material and associated outer cover material to stretch andmove freely and independently of each other, which may promote fit andcomfort. A snug fit about the wearer's legs provided by such elasticizedleg band portions 36 may serve to enhance containment capability of thewearable absorbent article.

One or more of waist band portions 34, 35 and leg band portions 36 maybe elasticized in the manner described above, or by other mechanisms.For example, elasticized band/strip material such as that used to formelastic waistbands and leg bands or other banding features ofconventional cloth underwear, briefs or other articles of clothing maybe separately produced, and affixed to the materials forming outer cover20 in any suitable manner, during the manufacture thereof.

In another example, one or more of waist band portions 34, 35 and legband portions 36 may be formed of elastic material simply affixed aboutthe leg opening and/or waist opening edges by use of adhesive and/orcompression bonding. In another example, an elastic strip material mayformed by affixing a plurality of strained elastomeric strands or stripsto one or more strips of unstrained nonwoven web material, or film. Whenthe resulting elastic strip material is allowed to relax, the unstrainedmaterial forms transverse rugosities that comprise gathered unstrainedmaterial, which will accommodate stretching of the elastic stripmaterial. By affixing the elastic strip material at one or more of waistband portions 34, 35 and/or leg band portions 36, the elastic stripmaterial may be used to form one or more of elasticized waist bandportions 34, 35 and/or leg band portions 36.

Anchoring Bands

Outer cover 20 also may include an anchoring supplement such asanchoring band 38 a and 38 b (collectively referred to as anchoringbands 38) disposed on or in the outer cover rear region 28 as indicatedin FIGS. 2A, 2B. As suggested in FIGS. 2A and 2B, anchoring band 38 maybe affixed along a layer, or disposed between layers, forming innersurfaces 25 and outer surfaces 24 of outer cover 20. Anchoring band 38may include an elastomeric or elasticized strip or band of material,affixed to outer cover 20 at locations proximate to its rearward cornersor proximate to fastening ears 29. Thus, anchoring band 38 may bepartially or substantially force-decoupled from the other layer(s) ofthe outer cover along its lateral length from the layer(s) forming theinner and outer surfaces of outer cover 20, via attachment to the outercover only by the ends of anchoring band 38, or only at a limited numberof selected intermediate lateral locations along anchoring band 38. Forexample, anchoring band 38 might be attached to outer cover 20 only atthe ends of anchoring band 38. In another example, anchoring band 38might be attached to outer cover 20 only at the ends and at the lateralcenter of anchoring band 38. This substantially force-decoupledarrangement allows anchoring band 38 and surrounding portions of outercover 20 to stretch and move substantially independently of one another,which may promote better fit and comfort. In another example, however,anchoring band 38 may be an elastic band, strip or strap laminated withor otherwise affixed to a layer of stretchable material forming eitherof or both the inner and outer surfaces of the outer cover, alongsubstantially the entire length of anchoring band 38.

When strained laterally by application to the wearer, anchoring band 38may serve to provide, or supplement, lateral tensile forces in thearticle about the wearer's waist, thereby tending to draw the waistopening snug, enhancing fit and enhancing securement of the wearableabsorbent article about the wearer's waist. The elastic modulus of theanchoring band may be higher than the elastic modulus of thesurrounding, adjacent, or coextensive outer cover materials.

An anchoring band, or system of one or more anchoring band members, mayhave any additional features described in, for example, co-pending U.S.patent applications Ser. Nos. 11/810,741; 11/810,708; 12/101,476;12/028,317; 11/810,745; 11/810,742; 11/810,734; 11/810,779; 11/810,715;11/810,733; 11/810,736; 11/810,777; and 11/599,862; 11/810,901 and11/599,851; 11/899,812; 12/204,844; 12/204,849; 12/204,854; 12/204,858;and 12/204,864; 11/899,810; 11/899,656; and 11/899,811; 11/899,812;12/204,844; 12/204,849; 12/204,854; 12/204,858; and 12/204,864; andco-pending U.S. applications Ser. Nos. 12/687,412, 12/687,528, and12/687,425, entitled, respectively, “REUSABLE WEARABLE ABSORBENTARTICLES WITH ANCHORING SYSTEMS,” “REUSABLE WEARABLE ABSORBENT ARTICLESWITH ANCHORING SUBSYSTEMS,” and “REUSABLE OUTER COVERS FOR WEARABLEABSORBENT ARTICLES,” by Donald C. Roe (Procter & Gamble Attorney DocketNos. 11225M, 11565 and 11566), filed on the same day hereof.

In another example, instead of, or in addition to, being orientedsubstantially laterally as suggested by the depicted location ofanchoring band 38 in FIGS. 2A and 2B, one or more members forminganchoring bands may be oriented diagonally between the longitudinal andlateral directions. For example, as suggested in FIG. 2A, a pair ofdiagonal anchoring bands 38 a may have respective waist ends thereofaffixed at a location area proximate to corners of the outer coverand/or fastening ears 29, and respectively extend toward both thelateral and longitudinal center of outer cover 20, as suggested in FIG.2A. The respective center ends of bands 38 a may be affixed to the outercover at locations proximate the lateral center of the outer cover assuggested in FIG. 2A, and bands 38 a may be either force-decoupled orforce-coupled to the outer cover along the lengths of bands 38 a, asdescribed above. In an example where an insert is connected to ananchoring band for additional longitudinal support as described furtherbelow, diagonal anchoring bands such as diagonal anchoring bands 38 amay serve to provide supplementary longitudinal tension along outercover 20, providing supplemental longitudinal support therewithin.

Examples of Possible Absorbent Insert Details

Examples of features of an absorbent insert 50 will be described withreference to FIGS. 3 and 4.

As noted above, FIG. 3 depicts a disposable absorbent insert 50 that mayform an inner component of a wearable absorbent article as describedherein, shown in perspective view as it might appear in a free-standing,relaxed state, apart from an outer cover. FIG. 4 depicts an example ofan insert 50 shown stretched out and laid flat (against elastic-inducedcontraction to a position similar to that shown in FIG. 3), body-facingsurfaces facing the viewer.

Insert 50 may have a topsheet 51 and backsheet 52 forming anenvelope-like enclosure for absorbent core materials such as thosedescribed further below. Topsheet 51 and backsheet 52 may be affixedtogether along longitudinal seams, and along lateral seams 69. Insert 50also may have longitudinal standing cuffs 53 affixed therealong.

Insert 50 also may include respective forward and rearward user graspstructures 59, 61. User grasp structures 59, 61 may be provided toenable the user to quickly and easily grasp insert 50 proximate itsrespective ends.

Referring to FIGS. 3 and 4, end support stiffeners 60 and 62 may beincluded. Such end support stiffeners may serve to aid the user inengaging the insert with the outer cover, and to help insert 50 maintainits intended shape and configuration while being worn beneath an outercover, i.e., help maintain the intended position and gasketing functionof the standing cuffs 53. End support stiffeners 60, 62 also may helpcontrol the corners of the insert regardless of the size, type orlocation of fastener components included on the insert. In addition toproviding resistance to longitudinal pull of cuff edges 58, end supportstiffeners 60, 62 may provide resistance to bending in any direction orplane.

Topsheet

Topsheet 51 may be formed of a liquid-permeable nonwoven web material.It may be desired that material forming topsheet 51 is compliant,soft-feeling, and non-irritating to the wearer's skin. It may be desiredthat at least a portion of topsheet 51 may be liquid pervious,permitting liquids to readily penetrate through its thickness. Asuitable topsheet may be manufactured from a wide range of materials,such as porous foams, reticulated foams, apertured plastic films, orwoven or nonwoven materials of natural fibers (e.g., wood or cottonfibers), synthetic fibers (e.g., polyester or polypropylene fibers), ora combination of natural and synthetic fibers. If topsheet 51 includesfibers, the fibers may be spunbond, carded, wet-laid, meltblown,hydroentangled, or otherwise processed as is known in the art.

One suitable material comprising a nonwoven web of staple-lengthpolypropylene fibers is manufactured by Veratec, Inc., a Division ofInternational Paper Company, of Walpole, Mass. under the designationP-8. Additional suitable materials comprising formed films are describedin U.S. Pat. Nos. 3,929,135; 4,324,246; 4,342,314; 4,463,045; and5,006,394. Other suitable topsheets 30 may be made in accordance withU.S. Pat. Nos. 4,609,518 and 4,629,643. Suitable examples of formedand/or apertured films may include products produced by The Procter &Gamble Company of Cincinnati, Ohio as DRI-WEAVE, and by TredegarCorporation, based in Richmond, Va., as FRESHFEEL. Suitable topsheetmaterials also may include laminates of films and nonwoven webs producedby Tredegar as COMFORTFEEL, COMFORTQUILT, SOFTQUILT and COMFORTAIRE.

In some circumstances it may be desired that at least a portion oftopsheet 51 is made of a hydrophobic material or is treated to behydrophobic in order to isolate the wearer's skin from liquids containedin absorbent core. If topsheet 51 is generally made of a hydrophobicmaterial, it may be desired that at least a portion of the upper surfaceof topsheet 51 is treated to be hydrophilic so that liquids willtransfer through the topsheet more rapidly. Topsheet 51 can be renderedhydrophilic by treating it with a surfactant or by incorporating asurfactant into the topsheet. Suitable methods for treating topsheet 51with a surfactant include spraying the topsheet material with thesurfactant and/or immersing the material into the surfactant. A moredetailed discussion of such a treatment and hydrophilicity is containedin U.S. Pat. Nos. 4,988,344 and 4,988,345. A more detailed discussion ofsome suitable methods for incorporating a surfactant in the topsheet canbe found in U.S. Statutory Invention Registration No. H1670. In anotherexample, however, topsheet 51 may include an apertured web or film whichis hydrophobic. This may be accomplished by foregoing the hydrophilizingtreatment step from the production process and/or applying a hydrophobictreatment to the topsheet material, such as a polytetraflouroethylenecompound like SCOTCHGUARD or a hydrophobic lotion composition, asdescribed below. In such examples, it may be desired that the aperturesbe large enough to allow the penetration of aqueous fluids like urinewithout significant resistance otherwise attributable to hydrophobicity.It may also be desired that the apertures have sufficient effective openarea and/or aperture size to allow the penetration of low-viscosityfecal material. Examples of topsheets meeting these requirements aredescribed in U.S. Pat. Nos. 5,342,338; 6,414,215; and 6,010,491.

Any portion of topsheet 51 may be coated with a lotion or skin carecomposition as is known in the art. Examples of suitable lotions includethose described in U.S. Pat. Nos. 5,607,760; 5,609,587; 5,635,191;5,643,588; 5,968,025 and 6,716,441. The lotion may function alone or incombination with another agent as the hydrophobizing treatment describedabove.

Topsheet 51 may also include or be treated with antibacterial agents,some examples of which are disclosed in U.S. application Ser. No.08/212,441, published as U.S. Statutory Invention Registration H1732.

Topsheet 51, backsheet 52 or any portion of the topsheet or backsheetmay be embossed and/or matte finished to provide a more cloth-likeappearance.

Topsheet 51 may be fully or partially elasticized or may beforeshortened so as to provide a void space between topsheet 51 andcore. Exemplary structures including elasticized or foreshortenedtopsheets are described in more detail in U.S. Pat. Nos. 4,892,536;4,990,147; 5,037,416; and 5,269,775.

Backsheet

Backsheet 52 is generally that outer liner portion of insert 50 formingthe garment-facing surface thereof, and prevents the exudates absorbedand contained within insert 50 from wicking through and soiling theouter cover. In some circumstances it may be desired that backsheet 52is substantially impervious to liquids.

Backsheet 52 may be formed of a film, a nonwoven, or a laminate of afilm and a nonwoven. Backsheet 52 may be formed of a substantiallyliquid-impermeable laminate or composite of film and non-woven web.Backsheet 52 may be formed of a substantially liquid impermeablenonwoven web, or laminate of nonwoven web and substantially liquidimpermeable film, so as to contain and isolate liquid exudates from theouter cover, outer clothing and/or environment of the wearer. At thesame time, backsheet 52 may be vapor permeable to provide forbreathability of the insert and the wearable absorbent article, reducinghumidity in the areas between the insert and the wearer's body, andhelping reduce the likelihood of skin irritation and/or rashes that mayresult from over-hydration of the skin.

The material forming backsheet 52 may include a thin plastic film suchas a thermoplastic film having a thickness of about 0.012 mm (0.5 mil)to about 0.051 mm (2.0 mils). Suitable backsheet materials also may bebreathable materials which permit vapors to escape while stillpreventing liquid from passing therethrough. Suitable examples mayinclude those manufactured by Tredegar Corporation, based in Richmond,Va., and sold under the trade names CPC2, X15306, X10962 and X10964film. Other examples may include microporous films such as manufacturedby Mitsui Toatsu Co., of Japan under the designation ESPOIR NO and byExxon Chemical Co., of Bay City, Tex., under the designation EXXAIRE,and monolithic films such as manufactured by Clopay Corporation,Cincinnati, Ohio under the name HYTREL blend P18-3097. Some additionalexamples may include breathable composite materials as described in PCTApplication No. WO 95/16746; and U.S. Pat. Nos. 5,938,648; 5,865,823;and 5,571,096. In other examples, backsheet 52 may comprise elastomericfilms, foams, strands, or combinations of these or other suitablematerials with nonwovens or synthetic films.

In certain embodiments, the backsheet may have a water vaportransmission rate (WVTR) of greater than about 2000 g/24 h/m², greaterthan about 3000 g/24 h/m², greater than about 5000 g/24 h/m², greaterthan about 6000 g/24 h/m², greater than about 7000 g/24 h/m², greaterthan about 8000 g/24 h/m², greater than about 9000 g/24 h/m², greaterthan about 10000 g/24 h/m², greater than about 11000 g/24 h/m², greaterthan about 12000 g/24 h/m², greater than about 15000 g/24 h/m², measuredaccording to WSP 70.5 (08) at 37.8° C. and 60% Relative Humidity. Ahigher WVTR may be desired in this particular application, since theinsert backsheet 52 will not form the outer surface of the wearablearticle, as a conventional disposable diaper backsheet would, butrather, will be covered by the one or more layers of the outer covermaterial(s)—which themselves may act in some circumstances to reduceWVTR of the composite structure.

Backsheet 52 may be joined to topsheet 51, absorbent core or any otherelement of insert 50 by any suitable attachment mechanism known in theart. For example, the attachment mechanism may include a continuous lineor layer of adhesive, a patterned layer of adhesive, or an array ofseparate lines, spirals, or spots of adhesive. One example of anattachment mechanism comprises an open pattern network of filaments ofadhesive as disclosed in U.S. Pat. No. 4,573,986. Other suitableattachment mechanisms include several lines of adhesive filaments whichare swirled into a spiral pattern, as is illustrated by the apparatusand methods shown in U.S. Pat. Nos. 3,911,173; 4,785,996; and 4,842,666.Adhesives which have been found to be satisfactory are manufactured byH. B. Fuller Company of St. Paul, Minn. and marketed as HL-1620 andHL-1358-XZP. Alternatively, the attachment mechanism may comprise heatbonds, pressure bonds, ultrasonic bonds, dynamic mechanical bonds, orany other suitable attachment mechanisms or combinations of theseattachment mechanisms known in the art.

It will be appreciated that the outer cover described above can beconstructed of materials and construction so as to bear and sustain amajority of the structural loading generally imposed upon a disposablediaper, by stretching and accommodation of the wearer's anatomicalfeatures and body movements, and by absorption, swelling and addedweight resulting from the wearer's exudations of waste. Thus, lesserrequirements for structural strength of an insert might be present withuse of such an outer cover, as compared with strength required of insidecomponents of a disposable diaper. Therefore, an article such asdescribed herein may include a disposable absorbent insert manufacturedfrom materials that are different from those ordinarily used in themanufacture of disposable diapers, such as petroleum-derived materials,e.g., polyethylene and polypropylene. For example, a disposableabsorbent insert having one or more of a topsheet, backsheet, standingcuffs and/or other components formed of products of wood, cotton, flax(linen), hemp, bamboo, or other cellulose fibers (e.g., paper), inaddition to the materials identified above, is contemplated. Ifresistance to aqueous liquid penetration or substantial liquidimpermeability is desired, e.g., for a backsheet and/or standing cuffs,a material formed of ordinarily hydrophilic fibers such as paper may becoated or impregnated with a hydrophobic material, such as askin-compatible oil or wax, to impart the desired resistance to aqueousliquid penetration. Each of the materials forming the insert may beselected so as to be dispersible in water or an aqueous solution,flushable, biodegradable and/or compostable (preferably to anagriculturally usable humus or soil amendment).

Absorbent Core

Insert 50 may have an absorbent core within the envelope-like structureformed by topsheet 51 and backsheet 52. Absorbent core may comprise anyabsorbent material which is generally compressible, conformable,non-irritating to the wearer's skin, and capable of absorbing andretaining liquids such as urine and other certain body exudates.Absorbent core may comprise a wide variety of liquid-absorbent materialscommonly used in disposable diapers and other absorbent articles such ascomminuted wood pulp, which is generally referred to as airfelt.Examples of other suitable absorbent materials include creped cellulosewadding; meltblown polymers, including coform; chemically stiffened,modified or cross-linked cellulosic fibers; tissue, including tissuewraps and tissue laminates; absorbent foams; absorbent sponges;superabsorbent polymers; absorbent gelling materials; or any other knownabsorbent material or combinations of materials.

Absorbent core may include liquid acquisition/distribution material, andstorage material. Generally, acquisition/distribution material may havecomparatively rapid absorption and wicking properties, but also may havelimited absorption capacity. Conversely, generally, storage material mayhave comparatively slower absorption and wicking properties, but alsomay have greater absorption capacity. Thus, acquisition/distributionmaterial may serve to rapidly absorb and distribute gushes of liquidsuch as urine, while storage material, having greater absorptioncapacity, may serve to absorb such liquid from theacquisition/distribution material and store it for the time needed untilthe insert may be replaced.

Absorbent wearable articles comprising at least one reusable element,such as a reusable outer cover, and one disposable element, such as adisposable absorbent insert adapted to be releasably and functionallyjoined to said reusable element, may be packaged together to enable aprospective user or caregiver to select an appropriate variants of eachelement for the intended use. For example, a package may contain one ormore reusable outer covers and one or more disposable absorbent insertsadapted to be used therewith. The inserts may be specifically designedto be used with the given outer cover. For example, the outer cover maybe sized for a specific range of wearers and the insert may havedimensions particularly relevant for use by a wearer of that size. Orthe outer cover may have one or more fastener elements disposed on itswearer-facing surface having a type, geometry, or spacing with which oneor more corresponding and complementary fastening elements on thegarment-facing surface of the insert are particularly adapted tofunction or align. Or the absorbent capacity of the insert may beadapted to acquire and contain a large enough amount of urine from agiven size wearer to enable the article to be suitable for reliable andconfident overnight usage. Generally, at least about 200 grams of urinecapacity, as measured by the Centrifuge Retention Capacity testdisclosed herein, is required for overnight usage of disposable insertsby infant or toddler wearers. More typically, the desirable overnightcapacity of a disposable insert may be at least about 225 grams, 250grams, 300 grams, or 350 grams. In order to minimize the usage ofmaterials, and the energy associated in their production which maycontribute to global warming, it is desirable that the absorbentefficiency of the insert be as high as possible. Generally, thenormalized capacity of the disposable absorbent insert is at least about8.0 g/g, and may be at least about 10.0 g/g.

In various embodiments of the present disclosure, a disposable absorbentinsert, configured for use with a reusable outer cover, can have aninsert absorbent capacity, measured according to the CentrifugeRetention Capacity Test, of at least 150 grams, at least 200 grams, atleast 250 grams, at least 300 grams, at least 350 grams, at least 400grams, or any integer value for grams between any of these values, orany range formed by any of these values.

In various embodiments of the present disclosure, a disposable absorbentinsert, configured for use with a reusable outer cover, can have anabsorbent insert mass of less than 60 grams, less than 50 grams, lessthan 40 grams, less than 30 grams, less than 20 grams, or any integervalue for grams between any of these values, or any range formed by anyof these values.

Absorbent core may be manufactured in a wide variety of sizes and shapes(e.g., rectangular, hourglass, “T”-shaped, etc.). The configuration andconstruction of absorbent core may also be varied (e.g., the absorbentcore(s) or other absorbent structure(s) may have varying caliper zones,hydrophilic gradient(s), a superabsorbent gradient(s), or lower averagedensity and lower average basis weight acquisition zones; or maycomprise one or more layers or structures). Examples of absorbentstructures for use as absorbent core may include those described in U.S.Pat. Nos. 4,610,678; 4,673,402; 4,834,735; 4,888,231; 5,137,537;5,147,345; 5,342,338; 5,260,345; 5,387,207; and 5,625,222.

To reduce the overall size and/or thickness of the absorbent core, andthereby improve wearer comfort and reduce the volume of disposable wastecreated by a soiled insert, it may be desired to construct an absorbentcore using the lowest volumes of core materials possible withinperformance constraints. Toward this end, examples of suitable materialsand constructions for a suitable absorbent core are described in, butare not limited to, copending U.S. applications Ser. Nos. 12/141,122;12/141,124; 12/141,126; 12/141,128; 12/141,130; 12/141,132; 12/141,134;12/141,141; 12/141,143; and 12/141,146. These applications generallydescribe absorbent core constructions that minimize or eliminate theneed for and inclusion of airfelt or other forms of cellulose fiber incombination with particles of superabsorbent polymer (hereinafter,“substantially airfelt-free cores”). Airfelt and other cellulose fiberhave been used as absorbent fillers in absorbent cores of disposablediapers. Such fiber possesses absorbent properties and imparts someabsorption capacity to an absorbent core, but also is included toprovide a structural matrix to hold dispersed particles ofsuperabsorbent polymer and/or absorbent gelling material. Whileinclusion of such particles enhances absorption capacity, keeping suchparticles suitably dispersed may be important to prevent the particlesfrom “gel-blocking” in use as they swell with absorbed liquid, causingloss of absorption capacity. The inclusion of airfelt or other cellulosefiber as a matrix for superabsorbent particles can serve to reduce orprevent gel-blocking. However, it also imparts bulk to an absorbentcore, even before absorption of any liquids.

An absorbent core having a portion that is substantially airfelt-freemay be disposed between the topsheet 51 and the backsheet 52. The coremay include a layer formed at least in part of a substrate, distributedabsorbent particles of a superabsorbent polymer or absorbent gellingmaterial, and a thermoplastic adhesive composition capturing thedistributed absorbent particles and adhering to at least portions of thesubstrate, thereby immobilizing the absorbent particles on or proximateto, and relative to, the substrate.

Features of an outer cover 20 as described herein provide for a wearableabsorbent article that has a relatively improved, garment-like (orunderwear-like) fit, comfort and appearance (as an outer garment orunder other clothes), as compared with many types of wholly disposablediapers currently available. If an outer cover 20 having such attributesis used with an insert 50 having an absorbent core incorporatingsubstantial amounts of airfelt or other cellulose fiber, the improved,garment-like fit, comfort and appearance provided by the outer cover 20may be compromised by the bulkiness of the insert. In order to betterpreserve some or most of the improved, garment-like fit, comfort andappearance of the outer cover 20, therefore, it may be desirable toconstruct absorbent core of insert 50 with features as described in oneor more of patent applications cited immediately above, which providefor a relatively thin absorbent core.

In addition to providing an absorbent core having reduced bulk, thesubstantially airfelt-free core may generally be more flexible than anabsorbent core containing substantial amounts of airfelt or othercellulose fiber. This enhanced flexibility may enable the core and theassociated insert to better conform about the wearer's body when in use,providing for improved comfort and less bulky appearance of the wearablearticle 10.

Additionally, by reducing or eliminating airfelt or other cellulosicfiber material, the substantially airfelt-free core reduces the amountof materials consumed in manufacturing, reduces the amount of space (andin some circumstances, weight) per unit which must be packaged andshipped, conserving resources in that regard, and reduces the amount ofmaterials and bulk which must be disposed of in connection withdisposing of a used/soiled insert.

Standing Cuffs

Insert 50 also may have a pair of longitudinal standing cuffs 53attached partially or entirely along the length thereof. Suitablelongitudinal standing cuffs (in various published examples identified as“leg cuffs”, “barrier cuffs” “gasketing cuffs,” etc., may be formed ofmaterials and construction such as described in, but not limited to,U.S. Pat. Nos. 6,786,895; 6,420,627; 5,911,713; 5,906,603; 5,769,838;5,624,425; 5,021,051 and 4,597,760; and copending U.S. PublishedApplication No. 2007/0239130 and U.S. application Ser. No. 11/195,272.As shown in FIG. 3, standing cuffs 53 may have one or more strands orstrips of cuff elastics 58 a, 58 b disposed longitudinally therealongcuff edges 58. If such cuff elastics 58 a, 58 b are pre-strained priorto being affixed to the web material forming standing cuffs 53,resulting longitudinal tensile forces therealong will cause the webmaterial forming standing cuffs 53 to gather as shown, and cause thecuffs to extend from the body of the insert (upwardly relative to FIG.3), or causing them to “stand”. This feature causes standing cuffs 53 toform a gasketing structure along the wearer's body when the articleincluding insert 50 is worn, longitudinally on either side of theanatomical features where waste is exuded. Thus, standing cuffs 53 mayserve to enhance the exudate containment capability of insert 50 and,and as a result, of the wearable absorbent article. As with backsheet52, standing cuffs 53 may be formed of a substantially liquidimpermeable web so as to contain and isolate liquid exudates from theouter cover, outer clothing and environment of the wearer. At the sametime, standing cuffs 53 may be vapor permeable to provide forbreathability of the insert and the wearable absorbent article, reducinghumidity in the areas between the insert and the wearer's body, andhelping reduce the likelihood of skin irritation and/or rashes that mayresult from over-hydration of the skin.

In another example, the material forming standing cuffs 53 may beintegral with the material forming backsheet 52, such as described in,by way of non-limiting example, copending U.S. Published App. No.2007/0239130. In this particular example, referring to and relative tothe view in FIG. 3, a continuous piece of material may form one standingcuff 53, wrap beneath the insert to form backsheet 52, and wrap up theother side to form the other standing cuff 53. This example of awraparound construction may provide improved liquid containmentcapability to insert 50, by eliminating seams along the outerliquid-containing surfaces that include standing cuffs 53 and backsheet52. Another example of this construction is depicted and described inU.S. Pat. No. 4,808,178.

In some circumstances, however, manufacturing and/or economicconstraints may discourage such construction, or else, it may bedesirable for the materials forming standing cuffs 53 and backsheet 52to have differing properties. For example, in some applications it maynot be deemed necessary for standing cuffs 53 to be substantially liquidimpervious, if they are otherwise formed of a nonwoven web materialcomprising closely situated hydrophobic fibers, which may still tend torepel and contain fluid, but may be generally more breathable thansubstantially liquid impervious laminates including films. In thisevent, improved strength and liquid containment attributes can still beimparted by having the material forming standing cuffs 53 wrap onlypartially beneath the lower longitudinal corners of the insert, andaffixed at seams beneath the insert, rather than at its outermost lowercorners as suggested by FIG. 3. One example of this construction isdepicted and described in U.S. application Ser. No. 11/158,563, and inparticular, FIG. 13 therein and associated descriptive text.

It is contemplated that an article of commerce including one or aplurality of outer covers and one or a plurality of inserts, asdescribed herein, may be prepared and sold as such, as described inco-pending U.S. patent application Ser. No. 12/687,538, filed Jan. 14,2010, and entitled, “Article of Commerce Including Two-Piece WearableAbsorbent Article,” by Donald C. Roe (Procter & Gamble Attorney DocketNo. 11564). For example, a package containing from one to 12, or more,outer covers, together with one or a plurality of associated inserts,may be assembled and sold together as packaged. The respective outercover(s) and inserts in a package may have matching/complementaryfastening systems, orientation indicia and/or alignment indicia asdescribed herein.

For such an article of commerce it may be desirable to determine a ratioof inserts to outer covers suitable to constitute a set of convenientnumbers of outer covers and inserts, respectively. For example, it maybe deemed suitable to include approximately a half day or day's supplyof inserts for each outer cover included in the set. Thus, for example,the article of commerce may include inserts and outer covers in a ratioof inserts to outer covers of 1:1, 2:1, 3:1, 4:1, 5:1 or even 6:1.Accordingly, for example, a package associating a set may include oneouter cover and 1, 2, 3, 4, 5 or 6 inserts; two outer covers and 2, 4,6, 8, 10 or 12 inserts; three outer covers and 3, 6, 9, 12, 15 or 18inserts, and so on. For a “starter” set for certain consumers such asfirst-time purchasers, or in other circumstances, it may be desirablefor a package to contain from 2 to 14 outer covers—which may correspondroughly to from one day's to one week's supply of clean outer coversavailable before laundering becomes necessary.

Bending Stiffness Test

Peak Bending Force and Total Stiffness are measured using a constantrate of extension tensile tester with computer interface (a suitableinstrument is an MTS Alliance under TestWorks 4 software, as availablefrom MTS Systems Corp., Eden Prairie, Minn.) using a load cell for whichthe forces measured are within 10% and 90% of the limit of the cell. Aplunger blade 600, shown in FIG. 5 (front view) and FIG. 6 (side view),is used for the upper movable test fixture. Base support platforms 700,shown in FIG. 7, are used as the lower stationary test fixture. Alltesting is performed in a conditioned room maintained at about 23° C.±2°C. and about 50%±2% relative humidity.

Components of the plunger 600 are made of a light weight material suchas aluminum to maximize the available load cell capacity. The shaft 601is machined to fit the tensile tester and has a locking collar 602 tostabilize the plunger and maintain alignment orthogonal to base supportplatforms 704. The blade 603, is 115 mm long 608 by 65 mm high 607 by3.25 mm wide 609, and has a material contact edge with a continuousradius of 1.625 mm. The bracket 604 is fitted with set screws 605 thatare used to level the blade and a main set screw 606 to firmly hold itin place after adjustment.

The bottom fixture 700 is attached to the tensile tester with the shaft701 and locking collar 702. Two horizontally movable support platforms704 are mounted on a rail 703. Each test surface 705 is 85 mm wide 706by 115 mm long (into plane of drawing) and made of polished stainlesssteel so as to have a minimal coefficient of friction. Each platform hasa digital position monitor 708 which reads the individual platformpositions, and set screws 707 to lock their position after adjustment.The two platforms 704 are square at the gap edge and the plate edgesshould be parallel front to back. The two platforms form a gap 709 withan adjustable gap width 710.

Accurately (±0.02 mm) align the plunger blade 603 so that it isorthogonal to the top surface of the support platforms 704 and exhibitsno skew relative to their gap edges. Using the position monitors 708,accurately set the gap 710 to 13.25±0.02 mm between the two gap edges ofthe support platforms 704, with the plunger blade 603 accurately (±0.02mm) centered in the gap. Set the gauge length from the bottom of theplunger blade 603 to the top surface of the support platform 704 to 15mm. Program the tensile tester to perform a compression test, collectingforce and extension data at an acquisition rate of 200 Hz as thecrosshead lowers at a rate of 500 mm/min for a total distance of 35 mm.

Precondition samples at about 23° C.±2° C. and about 50%±2% relativehumidity for 2 hours prior to testing. The outer cover article is openedand placed with the wearer-facing surface facing downward. Usingscissors remove the leg elastics, such that the article can be laidflat. Identify and mark the center of a sampling region which isrepresentative of the material making up the majority of the article,ensuring that it is free of seams, snaps, labels, etc. The samplingregion may often be located toward the back/crotch region of thearticle. With a hydraulic press and cutting die (76.2 mm square±0.1 mmand 8 mm deep), cut a specimen centered on this mark through all thelayers of the article, with the specimen's cut edges parallel andperpendicular to the longitudinal and lateral axis of the article.

Place the all layers of the specimen flat onto the surface of thesupport platform 704 over the gap 709 with the wearer-facing surfacefacing upward. Arrange the specimen 1009 under the blade 603 such thatabout ⅓ of the specimen is to the right of the blade and ⅔ to the left.The specimen is placed such that the direction corresponding to thelateral axis of the absorptive article it was harvested from is parallelto the length of the blade. Zero the load cell; start the tensile testerand the data acquisition. Program the software to calculate the maximumPeak Bending Force (N) from the constructed force (N) verses extension(m) curve, and record as “Lateral face-up”.

Remove the specimen from the gap 709, keeping the wearer-facing side up.Rotate the specimen 90° clockwise, and arrange the specimen under theblade 603 such that about ⅓ of the specimen is to the right of the bladeand ⅔ to the left, exposing a fresh area of the specimen for testing.Zero the load cell; start the tensile tester and the data acquisition.Record the maximum Peak Bending Force (N) as “Longitudinal face-up”.

Remove the specimen from the gap 709, keeping the wearer-facing side up.Rotate the specimen 90° counter-clockwise, and turn the specimen overfrom left to right, so that the wearer-facing surface is facingdownward. Arrange the specimen under the blade 603 such that about ⅓ ofthe specimen is to the right of the blade and ⅔ to the left, exposing afresh area of the specimen for testing. Zero the load cell; start thetensile tester and the data acquisition. Record the maximum Peak BendingForce (N) as “Lateral face-down”.

Remove the specimen from the gap 709, keeping the wearer-facing sidedown. Rotate the specimen 90° counter-clockwise, and arrange thespecimen under the blade 603 such that about ⅓ of the specimen is to theright of the blade and ⅔ to the left, exposing a fresh area of thespecimen for testing. Zero the load cell; start the tensile tester andthe data acquisition. Record the maximum Peak Bending Force (N) as“Longitudinal face-down”.

Calculate the Total Stiffness for a specimen by summing the “Lateralface-up”, “Longitudinal face-up”, “Lateral face-down” and “Longitudinalface-down” forces. Report the Total Stiffness to the nearest 0.001 N.Repeat the test and record the results for 10 samples. Calculate andreport the average Total Stiffness.

The dimensions and values disclosed herein are not to be understood asbeing strictly limited to the exact numerical values recited. Instead,unless otherwise specified, each such dimension is intended to mean boththe recited value and a functionally equivalent range surrounding thatvalue. For example, a dimension disclosed as “40 mm” is intended to mean“about 40 mm.”

Every document cited herein, including any cross-referenced or relatedpatent or application, is hereby incorporated herein by reference in itsentirety unless expressly excluded or otherwise limited. The citation ofany document is not an admission that it is prior art with respect toany invention disclosed or claimed herein or that it alone, or in anycombination with any other reference or references, teaches, suggests ordiscloses any such invention. Further, to the extent that any meaning ordefinition of a term in this document conflicts with any meaning ordefinition of the same term in a document incorporated by reference, themeaning or definition assigned to that term in this document shallgovern.

While particular embodiments of the present invention have beenillustrated and described, it would be obvious to those skilled in theart that various other changes and modifications can be made withoutdeparting from the spirit and scope of the invention. It is thereforeintended that the appended claims cover all such changes andmodifications, and that nothing in the foregoing description or thefigures, but rather, only the appended claims, limit the scope of theinvention.

1. A reusable outer cover, configured for use with a disposableabsorbent insert as a wearable absorbent article, wherein: the reusableouter cover has a bending stiffness peak force, measured according tothe Bending Stiffness Test; and the bending stiffness peak force of thereusable outer cover is less than or equal to 0.20 Newtons.
 2. Thereusable outer cover of claim 1, wherein the bending stiffness peakforce of the reusable outer cover is less than or equal to 0.18 Newtons.3. The reusable outer cover of claim 1, wherein the bending stiffnesspeak force of the reusable outer cover is less than or equal to 0.15Newtons.
 4. The reusable outer cover of claim 1, including a pluralityof layers.
 5. The reusable outer cover of claim 4, wherein each of thelayers has a bending stiffness peak force, measured according to theBending Stiffness Test, and the bending stiffness peak force of each ofthe layers is less than or equal to 0.10 Newtons.
 6. The reusable outercover of claim 4, wherein each of the layers has a bending stiffnesspeak force, measured according to the Bending Stiffness Test, and thebending stiffness peak force of each of the layers is less than or equalto 0.08 Newtons.
 7. The reusable outer cover of claim 1, including anouter layer material and an inner liner material.
 8. An absorbentarticle, comprising the reusable outer cover of claim 1 and a disposableabsorbent insert.